SCIENCE OF COMMON THINGS. 45 



Arch. Orders in architecture, Gothic structures. 



nitude ; the smaller wheel having to rise a steeper 

 curve. 



365 WJiat is an abutment f 



The vertical wall which sustains the base, or " spring" 

 of an arch. 



366 What is meant by an order in architecture f 



By an architectural order, we understand a certain 

 mode of arranging and decorating a column, and the 

 adjacent parts of the structure which it supports or 

 adorns. 



367 How many orders are recognised? 



five: the Doric, Ionic, and Corinthian, derived 

 from the Greeks; to these the Romans added two 

 others, known as the Tuscan and Composite. 



368 How do pilasters differ from columns f 



Only in their plan, which is square, as that of 

 columns is round : pilasters are attached to walls. 



369 What is a portico f 



A portico is a continued range of columns covered at 

 the top to shelter from the weather. The portico of the 

 temple at Palmyra was full four thousand feet long. 



370 What are balusters? 



Small columns, or pillars of wood, stone, <&c., used 

 in terraces or tops of buildings for ornament ; also to 

 support railing. When continued for some distance, 

 they form a balustrade. 



371 WJieredidthe Gothic order of architecture originate? 



Among the northern nations of Europe. After the 

 destruction of the Roman empire, it was introduced to 

 the exclusion of the Greek and Roman manner of 

 architecture. It seems particularly adapted to reli- 

 gious edifices. 



373 What are the characteristics of the Gothic architecture f 



Pointed arches, with greater height than breadth in 

 the proportions, with profuse ornament, chiefly de- 

 rived from an imitation of the leaves and flowerg of 

 plants. 



